The teachers encountered hundreds of state and federal police in full riot gear as they marched down the highway.

Videofootage was releasedWednesdayshowing the violent clashes that broke out between police and teachers in Mexico's southern state of Chiapas Tuesday—which left at least one teacher dead and six arrested.

Thousands of teachers from the National Coordinator of Education Workers (CNTE) union took to the streets Tuesday and started to march in the provincial capital Tuxtla.

The teachers were reportedly marching outside of the city towards the Mesoamerican School of Civil Protection, where the government had been forcing the teachers to undergo performance evaluations—what the teachers have long been vehemently against, saying it undermines their work.

The teachers reportedly encountered thousands of state and federal police wearing full riot gear as they marched along the highway. It is unclear how the clashes began, but police threw tear gas at the protesters who then returned the fire throwing rocks at the officials.

Video captured of the event by two nearby security cameras, and released by local Mexican media, showed violent clashes between the two sides, with minor explosions, and at one point a truck was lit on fire.

One teacher was killed in the crossfire, which lasted some two and a half hours, according to local media reports. The highway was left blocked off for at least 10 hours, causing massive traffic issues.

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